Number System + Algebraic Expressions Gr.9 Flashcards
What is a variable?
A placeholder for an unknown number.
What is a term?
A term is formed by the product of numbers or variables.
A term that does not include a variable is a _________.
Constant
How many terms does this have?
x - 3y + 7
3
Algebraic Expressions are usually written in ________ _____.
Descending order. Example: 2x^3 + 7x^2 - 4x + 9
When we know the value of a variable, we ___________ to evaluate an expression.
Substitute.
Write an Algebraic Expression for three times a number.
3x
Write an Algebraic Expression for a number divided by ten.
x / 10
Write an Algebraic Expression for six less than a number.
x - 6
What are real numbers?
All rational and irrational numbers, including whole numbers, fractions, and decimals.
Examples: -5, 0, 3.14, 2/3, √2, π
What are rational numbers?
Decimals or fractions that terminate or repeat.
Examples: 1/2, -3, 4.75, 0.333…, 7/1
What are Irrational Numbers?
Non-repeating and non-terminating decimals
Examples: π, √2, e, √5
What are integers?
…-4, -3, -2, -1, 0, 1, 2, 3, 4… no decimals
Examples: -4, -2, 0, 1, 3, 10
What are whole numbers?
0, 1, 2, 3, 4…
Examples: 0, 1, 2, 3, 10, 100
What are natural numbers?
1, 2, 3, 4…
Examples: 1, 2, 3, 4, 10, 100
Where would √49 be classified?
Integers.
Where would 1.25 be classified?
Rational numbers.
Where would -8 be classified?
Integers.
Where would √16 be classified?
Natural numbers.
Where would 2.666… be classified?
Rational numbers.
Where would 0 be classified?
Whole numbers.
Where would π be classified?
Irrational numbers.
